  <form action="<?php echo url_for('documentos/prueba2') ?>" method="POST">
  <table>
      <thead>
          <thead>
          <tr>
              <th colspan="2"><h2 id="titulo_form"><?php echo $title?></h2></th>                            
          </tr>
        </thead>          
      </thead>
      <tbody>
          <tr>
              <td><label>Nombre</label></td>
              <td><input type="text" name="id_beca" id="id_beca"/></td>
          </tr>
          <tr>
              <td><label>Cargo</label></td>
              <td><input type="text" name="id_user" id="id_user"/></td>
          </tr>
          <tr>
              <td><label>E-mail</label></td>
              <td><input type="text" name="id_user" id="id_user"/></td>
          </tr>          
          <tr>
              <td><label>Tel&eacute;fono</label></td>
              <td><input type="text" name="id_user" id="id_user"/></td>
          </tr>
          <tr><td colspan="2"><input id="boton" type="submit" value="Guardar" onclick="prueba()"/></td>             
          </tr>
      </tbody>
    <tfoot>
    <tr>   
        <td></td>
        <td></td>        
    </tr>   
    </tfoot>
  </table>
</form>